/* Basic reset and font styling */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --success-color: #10b981;
    --success-dark: #059669;
    --danger-color: #ef4444;
    --danger-dark: #dc2626;
    --warning-color: #f59e0b;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-tertiary: #f3f4f6;
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark mode variables */
body.dark-mode {
    --text-primary: #f3f4f6;
    --text-secondary: #d1d5db;
    --text-light: #9ca3af;
    --bg-primary: #1f2937;
    --bg-secondary: #111827;
    --bg-tertiary: #374151;
    --border-color: #4b5563;
}

body.dark-mode .bg-gradient {
    background: linear-gradient(135deg, #1f2937 0%, #111827 50%, #2d1b4e 100%);
}

body.dark-mode .header {
    background: rgba(31, 41, 55, 0.95);
    color: var(--text-primary);
}

body.dark-mode .task-form-card,
body.dark-mode .tasks-list-card {
    background: rgba(31, 41, 55, 0.95);
    color: var(--text-primary);
}

body.dark-mode .input-group input,
body.dark-mode #searchInput {
    background: rgba(17, 24, 39, 0.8);
    color: var(--text-primary);
    border-color: var(--border-color);
}

body.dark-mode .input-group input::placeholder,
body.dark-mode #searchInput::placeholder {
    color: var(--text-light);
}

body.dark-mode .task-card {
    background: rgba(31, 41, 55, 0.95);
    border-color: var(--border-color);
    color: var(--text-primary);
}

body.dark-mode .filter-btn {
    background: rgba(31, 41, 55, 0.95);
    border-color: var(--border-color);
    color: var(--text-secondary);
}

body.dark-mode .sort-btn {
    background: rgba(31, 41, 55, 0.95);
    border-color: var(--border-color);
    color: var(--text-secondary);
}

body.dark-mode .edit-input,
body.dark-mode .edit-select {
    background: rgba(17, 24, 39, 0.8);
    color: var(--text-primary);
    border-color: var(--border-color);
}

body.dark-mode .login-card {
    background: rgba(31, 41, 55, 0.95);
    color: var(--text-primary);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    margin: 0;
    padding: 0;
}

html {
    height: 100%;
    width: 100%;
}

.bg-gradient {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    opacity: 0.9;
    z-index: -1;
    animation: gradientShift 15s ease infinite;
}

@keyframes gradientShift {
    0%, 100% { opacity: 0.9; }
    50% { opacity: 1; }
}

/* Main container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    width: 100%;
}

/* Header bar */
.header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-radius: var(--radius-lg);
    padding: 1.5rem 2rem;
    margin-bottom: 2rem;
    box-shadow: var(--shadow-lg);
    animation: slideDown 0.5s ease;
    max-width: 1200px;
    margin-left: auto;
    margin-right: auto;
    width: 100%;
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.logo i {
    font-size: 2rem;
    color: var(--primary-color);
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}

.logo h1 {
    font-size: 1.75rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.header-buttons {
    display: flex;
    align-items: center;
    gap: 1rem;
}

/* Button Styles */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--radius-md);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: var(--shadow-sm);
    font-family: inherit;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn:active {
    transform: translateY(0);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: white;
}

.btn-primary:hover {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary-color));
}

.btn-success {
    background: linear-gradient(135deg, var(--success-color), var(--success-dark));
    color: white;
}

.btn-success:hover {
    background: linear-gradient(135deg, var(--success-dark), var(--success-color));
}

.btn-logout {
    background: linear-gradient(135deg, var(--danger-color), var(--danger-dark));
    color: white;
    display: none;
}

.btn-logout:hover {
    background: linear-gradient(135deg, var(--danger-dark), var(--danger-color));
}

.btn-dark-mode {
    background: linear-gradient(135deg, #f59e0b, #f97316);
    color: white;
    display: none;
}

.btn-dark-mode:hover {
    background: linear-gradient(135deg, #f97316, #f59e0b);
}

.btn-large {
    padding: 1rem 2rem;
    font-size: 1.1rem;
}

/* Login Section - Bulletproof Centering */
#login-section {
    position: fixed !important;
    inset: 0 !important;
    display: flex !important;
    justify-content: center !important;
    align-items: center !important;
    z-index: 1000 !important;
    animation: fadeIn 0.6s ease;
    overflow: hidden;
}

#login-section[style*="display: none"] {
    display: none !important;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: scale(0.95);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

.login-card {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-radius: var(--radius-lg);
    padding: 3rem;
    box-shadow: var(--shadow-xl);
    max-width: 450px;
    width: 90%;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
    position: relative;
    transform: none;
}

.login-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    animation: bounce 2s ease-in-out infinite;
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.login-icon i {
    font-size: 2.5rem;
    color: white;
}

.login-card h2 {
    font-size: 2rem;
    font-weight: 700;
    margin: 0;
    color: var(--text-primary);
    text-align: center;
}

.login-card p {
    color: var(--text-secondary);
    margin: 0;
    font-size: 1.05rem;
    text-align: center;
}

.login-card .btn {
    width: fit-content;
}

/* Tasks Section */
#tasks-section {
    display: none;
    animation: fadeIn 0.6s ease;
}

.section-title {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
}

.section-title i {
    color: var(--primary-color);
}

/* Task Form Card */
.task-form-card {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-radius: var(--radius-lg);
    padding: 2rem;
    margin-bottom: 2rem;
    box-shadow: var(--shadow-lg);
    animation: slideUp 0.5s ease;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.task-form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.input-group {
    position: relative;
    display: flex;
    align-items: center;
}

.input-icon {
    position: absolute;
    left: 1rem;
    color: var(--text-light);
    font-size: 1.1rem;
    pointer-events: none;
}

.input-group input {
    width: 100%;
    padding: 1rem 1rem 1rem 3rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-family: inherit;
    transition: var(--transition);
    background: white;
}

.input-group input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.char-count {
    color: var(--text-light);
    font-size: 0.85rem;
    margin-top: -0.5rem;
}

.form-row {
    display: flex;
    gap: 1rem;
    align-items: flex-start;
}

.date-input {
    flex: 1;
}

.date-input input {
    padding: 1rem 1rem 1rem 3rem;
}

.form-row .btn {
    white-space: nowrap;
    padding: 1rem 2rem;
}

/* Tasks List Card */
.tasks-list-card {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-radius: var(--radius-lg);
    padding: 2rem;
    box-shadow: var(--shadow-lg);
    animation: slideUp 0.6s ease;
}

#tasksList {
    margin-top: 1.5rem;
}

/* Search Box */
.search-box {
    position: relative;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
}

.search-icon {
    position: absolute;
    left: 1rem;
    color: var(--text-light);
    font-size: 1.1rem;
    pointer-events: none;
    z-index: 1;
}

#searchInput {
    width: 100%;
    padding: 0.9rem 1rem 0.9rem 3rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-family: inherit;
    transition: var(--transition);
    background: white;
}

#searchInput:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

#searchInput::placeholder {
    color: var(--text-light);
}

.clear-search-btn {
    position: absolute;
    right: 1rem;
    background: transparent;
    border: none;
    color: var(--text-light);
    cursor: pointer;
    font-size: 1.1rem;
    padding: 0.5rem;
    transition: var(--transition);
    z-index: 2;
}

.clear-search-btn:hover {
    color: var(--primary-color);
    transform: scale(1.2);
}

.search-result-info {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 1rem;
    padding: 0.75rem 1rem;
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.search-result-info i {
    color: var(--primary-color);
}

/* Filter Section */
.filter-section {
    margin-bottom: 2rem;
}

.filter-buttons {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
    justify-content: center;
}

.filter-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.25rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    background: white;
    color: var(--text-secondary);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.filter-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    opacity: 0;
    transition: var(--transition);
    z-index: 0;
}

.filter-btn > * {
    position: relative;
    z-index: 1;
}

.filter-btn:hover {
    border-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.filter-btn.active {
    border-color: var(--primary-color);
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: white;
    box-shadow: var(--shadow-md);
}

.filter-btn.active::before {
    opacity: 1;
}

.filter-btn i {
    font-size: 1rem;
}

.filter-count {
    background: rgba(0, 0, 0, 0.1);
    padding: 0.2rem 0.6rem;
    border-radius: 12px;
    font-size: 0.85rem;
    font-weight: 700;
    min-width: 24px;
    text-align: center;
}

.filter-btn.active .filter-count {
    background: rgba(255, 255, 255, 0.25);
}

.filter-btn:hover:not(.active) .filter-count {
    background: rgba(99, 102, 241, 0.1);
    color: var(--primary-color);
}

/* Task Controls */
.task-controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid var(--border-color);
    flex-wrap: wrap;
    gap: 1rem;
}

.sort-buttons {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.sort-btn {
    background: white;
    border: 2px solid var(--border-color);
    padding: 0.5rem 1rem;
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
}

.sort-btn:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.sort-btn i {
    font-size: 0.9rem;
}

.task-count {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
    font-weight: 600;
    font-size: 0.95rem;
}

.task-count i {
    color: var(--primary-color);
}

/* Tasks Grid */
.tasks-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.5rem;
}

/* Task Card */
.task-card {
    background: white;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    transition: var(--transition);
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.task-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--primary-light));
    transform: scaleX(0);
    transition: var(--transition);
}

.task-card:hover {
    border-color: var(--primary-color);
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.task-card:hover::before {
    transform: scaleX(1);
}

.task-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.status-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.4rem 0.9rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.status-done {
    background: linear-gradient(135deg, #d1fae5, #a7f3d0);
    color: #065f46;
}

.status-progress {
    background: linear-gradient(135deg, #dbeafe, #bfdbfe);
    color: #1e40af;
}

.status-pending {
    background: linear-gradient(135deg, #fef3c7, #fde68a);
    color: #92400e;
}

.status-blocked {
    background: linear-gradient(135deg, #fee2e2, #fecaca);
    color: #991b1b;
}

.task-card-actions {
    display: flex;
    gap: 0.5rem;
}

.icon-btn {
    background: transparent;
    border: none;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
    color: var(--text-secondary);
}

.icon-btn:hover {
    background: var(--bg-secondary);
    color: var(--primary-color);
    transform: scale(1.1);
}

.delete-btn:hover {
    background: #fee2e2;
    color: var(--danger-color);
}

.task-card-body {
    padding-top: 0.5rem;
}

.task-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 1rem;
    line-height: 1.4;
    word-wrap: break-word;
}

.task-meta {
    display: flex;
    align-items: center;
    gap: 1rem;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.task-date {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.task-date.overdue {
    color: var(--danger-color);
    font-weight: 600;
}

.task-date i {
    font-size: 0.9rem;
}

/* Task Card Edit Mode */
.task-card-edit {
    padding: 0.5rem;
}

.edit-form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.form-group label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 600;
    color: var(--text-primary);
    font-size: 0.9rem;
}

.form-group label i {
    color: var(--primary-color);
    font-size: 0.85rem;
}

.btn-secondary {
    background: linear-gradient(135deg, #9ca3af, #6b7280);
    color: white;
}

.btn-secondary:hover {
    background: linear-gradient(135deg, #6b7280, #9ca3af);
}

/* Edit Mode Styles */
.edit-input {
    width: 100%;
    padding: 0.75rem;
    font-size: 0.95rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-family: inherit;
    transition: var(--transition);
}

.edit-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.edit-select {
    width: 100%;
    padding: 0.75rem;
    font-size: 0.95rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-family: inherit;
    cursor: pointer;
    transition: var(--transition);
    background: white;
}

.edit-select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.edit-actions {
    display: flex;
    gap: 0.75rem;
    margin-top: 0.5rem;
}

.edit-actions .btn {
    flex: 1;
}

.edit-save {
    background: linear-gradient(135deg, var(--success-color), var(--success-dark));
}

.edit-save:hover {
    background: linear-gradient(135deg, var(--success-dark), var(--success-color));
}

.edit-cancel {
    background: linear-gradient(135deg, #9ca3af, #6b7280);
}

.edit-cancel:hover {
    background: linear-gradient(135deg, #6b7280, #9ca3af);
}

/* Responsive */
@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }

    .header {
        padding: 1rem;
    }

    .logo h1 {
        font-size: 1.25rem;
    }

    .logo i {
        font-size: 1.5rem;
    }

    .btn span {
        display: none;
    }

    .btn {
        padding: 0.75rem;
    }

    .task-form-card,
    .tasks-list-card {
        padding: 1.5rem;
    }

    .section-title {
        font-size: 1.25rem;
    }

    .form-row {
        flex-direction: column;
    }

    .form-row .btn {
        width: 100%;
    }

    .login-card {
        padding: 2rem;
        margin: 1rem;
    }

    .login-card h2 {
        font-size: 1.5rem;
    }

    .tasks-grid {
        grid-template-columns: 1fr;
    }

    .task-controls {
        flex-direction: column;
        align-items: flex-start;
    }

    .sort-buttons {
        width: 100%;
        justify-content: space-between;
    }

    .sort-btn {
        flex: 1;
        justify-content: center;
        padding: 0.6rem 0.5rem;
        font-size: 0.8rem;
    }

    .sort-btn span {
        display: none;
    }

    /* Filter buttons on mobile */
    .filter-buttons {
        gap: 0.5rem;
    }

    .filter-btn {
        flex: 1;
        min-width: 0;
        padding: 0.6rem 0.75rem;
        font-size: 0.85rem;
        justify-content: center;
    }

    .filter-btn span:not(.filter-count) {
        display: none;
    }

    .filter-count {
        margin-left: 0;
    }
}

@media (max-width: 480px) {
    .header-content {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }

    .logo {
        flex-direction: column;
        gap: 0.5rem;
    }

    .task-card {
        padding: 1rem;
    }

    .task-title {
        font-size: 1rem;
    }
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--text-secondary);
}

.empty-state i {
    font-size: 4rem;
    color: var(--text-light);
    margin-bottom: 1rem;
}

.empty-state h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.empty-state p {
    font-size: 1rem;
}

/* Loading Animation */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Scrollbar Styling */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
    border-radius: 5px;
}

::-webkit-scrollbar-thumb {
    background: var(--primary-color);
    border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary-dark);
}